Вопрос школьника по предмету Математика
Катер проплыл между Двумя пристанями по течению реки за 1,5 ч а против течения на 15 минут дольше. Чему равна собственная скорость катера, если скорость течения реки равна равна 2 км/ч.
Ответ учителя по предмету Математика
пусть х кмч — собственная скорость катера. тогда х+2 -скорость по течению, а х-2 — скорость против течения. 1,5*(х+2) -путь по течению. (1,5+0,25)*(х-2)- путь против течения. составим уравнение 1,5*(х+2)=1,75*(х-2)
1.5х+3=1,75х-3,5
3+3,5=1,75х-1,5х
0,25х=6,5
х=26
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